Jeep Grand Cherokee WK. Manual — part 511

U1000–CAN B BUS (+) CIRCUIT– MEMORY MIRROR MODULE

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POWER MIRRORS - ELECTRICAL DIAGNOSTICS

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U1000–CAN B BUS (+) CIRCUIT– MEMORY MIRROR MODULE (CONTINUED)

For the Power Memory Mirror System circuit diagram (Refer to 8 - ELECTRICAL/POWER MIRRORS - SCHEMAT-
ICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the ignition in the run position.

•

Set Condition:
If the Driver / Passenger Memory Mirror Module senses that the (D55) Can B Bus (+) circuit is either open, or
shorted to voltage, or shorted to ground.

Possible Causes

FOR THE DRIVER MEMORY MIRROR SYSTEM:

ACTIVE CAN B BUS DTCs IN FRONT CONTROL MODULE (FCM)

(D55) CAN B BUS (+) CIRCUIT OPEN TO DRIVER MEMORY MIRROR MODULE

DRIVER MEMORY MIRROR MODULE

FOR THE PASSENGER MEMORY MIRROR SYSTEM:

ACTIVE CAN B BUS DTCs IN FRONT CONTROL MODULE (FCM)

(D55) CAN B BUS (+) CIRCUIT OPEN TO PASSENGER MEMORY MIRROR MODULE

PASSENGER MEMORY MIRROR MODULE

NOTE: Since this DTC can set in the Driver Door Module (DDM) and in the Passenger Door Module (PDM)
this procedure addresses both systems’ circuits and components. Select only that which applies to the sys-
tem you are diagnosing.

Diagnostic Test

1.

TEST FOR INTERMITTENT CONDITION

Turn the ignition on.

With the scan tool, record and erase DTCs.

Cycle the ignition from on to off 3 times.

Turn the ignition on.

With the scan tool, read DTCs.

Does the scan tool display: U1000 CAN B BUS (+) CIRCUIT?

Yes

>> Go To 2

No

>> The conditions that caused this code to set are not present at this time. Using the wiring diagram/sche-

matic as a guide, inspect the wiring and connectors.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES - STANDARD PROCEDURE).

2.

CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE FRONT CONTROL MODULE (FCM)

With the scan tool, read Front Control Module (FCM) DTCs

Does the scan tool display any active CAN B BUS related DTCs?

Yes

>> Diagnose and repair the DTC(s). (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES -

DIAGNOSIS AND TESTING).

No

>> Go To 3

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POWER MIRRORS - ELECTRICAL DIAGNOSTICS

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U1000–CAN B BUS (+) CIRCUIT– MEMORY MIRROR MODULE (CONTINUED)

3.

CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN BETWEEN THE FRONT CONTROL MODULE
& THE DRIVER / PASSENGER MEMORY MIRROR MODULE

For the Driver Memory Mirror System, proceed as follows:

•

Turn the ignition off.

•

Disconnect the Driver Memory Mirror Module C1 connector.

•

Disconnect the Front Control Module C1 connector.

•

Measure the resistance of the (D55) Can B Bus (+) circuit
between the Front Control Module C1 connector and the Driver
Memory Mirror Module C1 connector.

For the Passenger Memory Mirror System, proceed as follows:

•

Turn the ignition off.

•

Disconnect the Passenger Memory Mirror Module connector.

•

Disconnect the Front Control Module C1 connector.

•

Measure the resistance of the (D55) Can B Bus (+) circuit
between the Front Control Module C1 connector and the Passen-
ger Memory Mirror Module connector.

Is the resistance below 2.0 ohms?

Yes, Driver MMM

Replace the Driver Memory Mirror Module in accordance
with the Service Information.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8
- ELECTRICAL/ELECTRONIC CONTROL MODULES -
STANDARD PROCEDURE).

Yes, Passenger MMM

Replace the Passenger Memory Mirror Module in accor-
dance with the Service Information.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES - STANDARD PROCEDURE).

No

>> Repair the (D55) Can B Bus (+) circuit for an open.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES - STANDARD PROCEDURE).

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POWER MIRRORS - ELECTRICAL DIAGNOSTICS

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U1001–CAN B BUS (-) CIRCUIT– MEMORY MIRROR MODULE

WK

POWER MIRRORS - ELECTRICAL DIAGNOSTICS

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